The Westlake Match Seatbox Arm & Upright 30cm is the ideal fitting for any seat box, offering a stable rear rest fitting, which can be adjusted to suit. The 30cm arm has a hand wheel -lock fitting to secure it on the leg, while the upright can be locked in place by tightening the wheel nut that secures the clamp. The upright has a 3/8s brass thread which will take any modern day rest fitting. Can be used as a rear rest, pole section roost, or any other seat box accessory, which has a screw fitting. (Seatbox shown in image is not included.) Length 30cmArm fitting.Upright 17cm.Upright with brass thread.Fits rear or front legs.Fits 25-30-36mm legs.